Plastic bags made of high density polyethylene (HDPE) are used in many different settings, such as supermarkets, department stores, and similar applications. The plastic bags may be dispensed from flat packs or may be wound on rolls. The bags made of thin, flexible HDPE films tend to be very difficult to open because HDPE film has a very low surface coefficient of friction (COF). The front and rear panels of the plastic bag often stick or cling to each other, making it difficult for a customer to identify the opening of the bag and to separate the front and rear panels to open the bag due to the low COF of the film. Thus, it would be beneficial to have a plastic bag configured for easy opening.
Several attempts have been made to provide easy opening for bags. For example, U.S. Pat. No. 5,894,947 uses embossment or piercing to enhance gripping. However, embossment or piercing weakens the strength of the film. U.S. Publication 2003/0138171 uses a non-slip coating, a zipper with a co-extruded flange, or embossment. However, applying a coating is an extra process that adds to the time and cost to manufacture the bag, the co-extruded flange requires that the bag includes a special zipper, and, as already stated, embossment weakens the strength of the film. U.S. Pat. No. 7,950,851 uses rib profiles to enhance grip to tear a bag. However, extra materials are needed to form the raised ribs from the bag walls. Accordingly, it would be beneficial to have an improved plastic bag configured for easy opening.